... The adaptive micro interface allows microcontrollers, such as the 68HC11, 80C51 and TMS370C50, to access the MT8889C/MT8889C-1 internal registers. Input Configuration The input arrangement of the MT8889C/MT8889C-1 provides a differential-input operational amplifier as well as a bias source (V ), which is used to bias the Ref inputs ...

... Figure 7 with a description of the events in Figure 9. Call Progress Filter A call progress mode, using MT8889C-1, can be selected allowing the detection of various tones, which identify the progress of a telephone call on the network. tone input and DTMF input are common, however, call progress tones can only be detected when CP EVENTS A ...

... GUARD TIME, TONE ABSENT. GTA DTMF Generator The DTMF transmitter employed in the MT8889C/ MT8889C-1 is capable of generating all sixteen standard DTMF tone pairs with low distortion and high accuracy. All frequencies are derived from an external 3.579545 MHz crystal. The sinusoidal waveforms for the individual tones are digitally synthesized using row and column programmable dividers and switched capacitor D/A converters ...

... Table 2. Actual Frequencies Versus Standard Distortion Calculations The MT8889C/MT8889C-1 is capable of producing precise tone bursts with minimal error in frequency (see Table 2). The internal summing amplifier is followed by a first-order lowpass switched capacitor filter to minimize intermodulation distortion for a single tone can be calculated using ...

... RS0 CS * Microprocessor based systems can inject undesirable noise into the supply rails. The performance of the MT8889C/MT8889C-1 can be optimized by keeping noise on the supply rails to a minimum. The decoupling capacitor (C3) should be connected close to the device and ground loops should be avoided. STATUS FLAG CLEARED Interrupt is inactive ...

... MT8889C/MT8889C-1 MMD6150 (or equivalent) TEST POINT 130 Test load for D0-D3 pins A software reset must be included at the beginning of all programs to initialize the control registers after power up. The initialization procedure should be implemented 100ms after power up. Description: 1) Read Status Register 2) Write to Control Register 3) Write to Control Register ...